MONTAGNIAC, a considerable town of Asia, in Natolia, and in the province of Bee-Sangel, on the sea of Marmora. It carries on a great trade, especially in fruits, and is seated on a bay of the same name, 12 miles from Bursa, and 60 south-east of Constantinople. E. Long. 29. 40. N. Lat. 40. 20.